336 NON-SACCHAROMYCETES OR DOUBTFUL YEASTS 



On decoctions of "koji," this species forms a thin scum smooth, 

 shiny and dry. This is folded and in old cultures becomes farina- 

 ceous. On beer wort, the scum forms slowly and has a dull aspect. 

 This yeast produces no fermentation of dextrose, levulose, d-galactose, 

 lactose, maltose, saccharose, melibiose, mannose and raffinose. 



BRUSENDORFS MYCODERMA 



Isolated by Brusendorf 1 from potatoes from the Danish Antilles, 

 this species forms on hop wort a thick resistant scum with a dry 

 appearance. The cells are oval, often slightly elongated and placed in 

 chains of three or four individuals. They are 5 to 10 JJL long and 2 

 to 5/x wide. The cultures often have an acid odor due to formic 

 acid produced by the yeast. 



SACCHAROMYCES MYCODERMA I. Wehmer 2 



This yeast was isolated from fermenting sourkraut along with 

 Saccharomyces brassicae I and II. The cells are always small (3.6 

 to 5 jit) with almost always a refractive granule of variable size. They 

 provoke no fermentation. On cabbage decoction the scum is white, 

 folded and tenacious. On gelatin, with cabbage decoction added, 

 this yeast forms a fine sediment, white in color. This species de- 

 stroys lactic acid energetically. 



SACCHAROMYCES MYCODERMA II. Wehmer 



Wehmer 3 isolated this species from the same source as the pre- 

 ceding one. It has ellipsoidal cells, never spherical but rather large 

 (8.4 4.8 X 6ju). No fermentation is induced. On cabbage de- 

 coction the scum is thin and a dull gray. In old cultures, it 

 becomes folded. This species quickly destroys lactic acid. 



DUCLAUX'S YEAST. (Mycolevure) 



This yeast was discovered by DuClaux 4 in Raulin's solution ex- 

 posed to the air, where it appeared spontaneously. It develops with 

 a regular scum which is folded when it lacks space to spread out. 

 Under such conditions, it becomes very thick. The scum is formed of 

 oval cells more or less granular. They are sometimes as large as 



1 Brusendorf. Ein Ameinsaure bildende Mycoderma. Cent. Bakt. 23, 1909. 



2 Wehmer, C. Untersuch. iiber Sauerkrautgarung. Cent. Bakt. 14, 1905. 



3 Wehmer, C. See reference for Saccharomyces mycoderma I. 



4 DuClaux, E. Traite de Microbiologie. Fermentation alcoolique. Vol. 3. 

 Masson and Co., Paris, 1900. 



